mango said it that juice that claire was getting shot into her tummy must be also something verry imortant.
Not the shots - the implant.
Claire was implanted with something to make her feel ill, so that Juliet could later administer a cure and gain the Losties' trust.
Ben made Juliet go along with this, but Juliet later told Jack about the plan.
There's never been any mention of the implant being removed, nor how it worked.